Effects of COlaser on chromosomal aberration in the root tip cells of rice

<正> Seeds of japonica rice cv.Zhenuo 2 with twodifferent physiological states（dry seeds withwater content 13% and wet seeds soaked in thewater for 36 h）were irradiated by CO2 laser infour different power-densities and durations re-spectively.The treatment irradiated with 200GY of 60Co γ-rays was considered as control.The flesh root tips were cut and fixed inCarnoy's fluid for cytological examination.